rs1064796675

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM2PM5PP3_ModeratePP5

The NM_005993.5(TBCD):​c.880C>T​(p.Arg294Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000682 in 1,611,742 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R294Q) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 31)
Exomes 𝑓: 0.0000069 ( 0 hom. )

Consequence

TBCD
NM_005993.5 missense

Scores

9
9
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:2

Conservation

PhyloP100: 2.68
Variant links:
Genes affected
TBCD (HGNC:11581): (tubulin folding cofactor D) Cofactor D is one of four proteins (cofactors A, D, E, and C) involved in the pathway leading to correctly folded beta-tubulin from folding intermediates. Cofactors A and D are believed to play a role in capturing and stabilizing beta-tubulin intermediates in a quasi-native confirmation. Cofactor E binds to the cofactor D/beta-tubulin complex; interaction with cofactor C then causes the release of beta-tubulin polypeptides that are committed to the native state. [provided by RefSeq, Jul 2008]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr17-82800927-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 449795.Status of the report is criteria_provided_single_submitter, 1 stars.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.888
PP5
Variant 17-82800926-C-T is Pathogenic according to our data. Variant chr17-82800926-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 423874.We mark this variant Likely_pathogenic, oryginal submissions are: {Pathogenic=1, Uncertain_significance=2}.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
TBCDNM_005993.5 linkuse as main transcriptc.880C>T p.Arg294Trp missense_variant 9/39 ENST00000355528.9

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
TBCDENST00000355528.9 linkuse as main transcriptc.880C>T p.Arg294Trp missense_variant 9/391 NM_005993.5 P1Q9BTW9-1

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
152074
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.00000809
AC:
2
AN:
247086
Hom.:
0
AF XY:
0.00000744
AC XY:
1
AN XY:
134330
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.0000328
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000894
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000685
AC:
10
AN:
1459668
Hom.:
0
Cov.:
31
AF XY:
0.00000413
AC XY:
3
AN XY:
726160
show subpopulations
Gnomad4 AFR exome
AF:
0.0000300
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000253
Gnomad4 SAS exome
AF:
0.0000116
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000630
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000658
AC:
1
AN:
152074
Hom.:
0
Cov.:
31
AF XY:
0.00
AC XY:
0
AN XY:
74282
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000312
Hom.:
0
Bravo
AF:
0.00000756

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:1Uncertain:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Pathogenic:1Uncertain:1
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpSep 15, 2023ClinVar contains an entry for this variant (Variation ID: 423874). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt TBCD protein function. For these reasons, this variant has been classified as Pathogenic. This missense change has been observed in individual(s) with progressive early-onset encephalopathy with brain atrophy and thin corpus callosum (PMID: 32705489). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. It has also been observed to segregate with disease in related individuals. This variant is present in population databases (no rsID available, gnomAD 0.003%). This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 294 of the TBCD protein (p.Arg294Trp). -
Uncertain significance, criteria provided, single submitterclinical testingGeneDxMar 06, 2017The R294W variant in the TBCD gene has not been reported previously as a pathogenic variant, nor as a benign variant, to our knowledge. The R294W variant is not observed in large population cohorts (Lek et al., 2016; 1000 Genomes Consortium et al., 2015; Exome Variant Server). The R294W variant is a non-conservative amino acid substitution, which is likely to impact secondary protein structure as these residues differ in polarity, charge, size and/or other properties. This substitution occurs at a position that is conserved across species. In silico analysis predicts this variant is probably damaging to the protein structure/function. We interpret R294W as a variant of uncertain significance. -
Early-onset progressive diffuse brain atrophy-microcephaly-muscle weakness-optic atrophy syndrome Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingFulgent Genetics, Fulgent GeneticsOct 31, 2018- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.44
BayesDel_addAF
Pathogenic
0.24
D
BayesDel_noAF
Pathogenic
0.21
CADD
Pathogenic
30
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.47
T;.
Eigen
Pathogenic
0.73
Eigen_PC
Uncertain
0.65
FATHMM_MKL
Uncertain
0.92
D
LIST_S2
Uncertain
0.97
D;D
M_CAP
Pathogenic
0.40
D
MetaRNN
Pathogenic
0.89
D;D
MetaSVM
Uncertain
0.51
D
MutationAssessor
Pathogenic
3.7
H;.
MutationTaster
Benign
1.0
D;D;D
PrimateAI
Uncertain
0.63
T
PROVEAN
Pathogenic
-5.7
D;.
REVEL
Pathogenic
0.69
Sift
Uncertain
0.0020
D;.
Sift4G
Uncertain
0.0040
D;D
Polyphen
1.0
D;.
Vest4
0.86
MutPred
0.60
Gain of catalytic residue at L292 (P = 0.0037);Gain of catalytic residue at L292 (P = 0.0037);
MVP
0.92
MPC
1.0
ClinPred
1.0
D
GERP RS
5.3
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.8
Varity_R
0.44
gMVP
0.73

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs1064796675; hg19: chr17-80758802; API